Trenching-machine



H. J. BENTSON. TRENCHING MACHINE. APPLICATION FILED SEPT-1'5, r916.

Patented J 2111.6, 1920. I SHEET I L3Q7A18.

6 SHEETS- H. J. BENTSON'.

TRENCHiNG MACHINE. APPLICATION men SEPT- 15. 1910- fizese:

H. BENTSON.

TRENCHIN'G MACHINE. APPLICATION FILED SEPT-15,1916.

Patented J an. 6, 1920.

6 SHEETSSHEET 3- H. J. BENTSON. v TRENCHING MACHINE.

APPLICATION man SEPT. 15, I916- 1,327,41, Patented Jan. 6,1920.

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H. J. BENTSON.

TRENCHING MACHINE. APPLICATION FILED SEPT-15.1916- Patented Jan. 6,1920.

6 SHEETSSHEET 5.

H. J. BENTSON. mwcmwe MACHINE. APPLICATION FILED SEPT-15,19l6-1,327,418, Patented Jan. 6, 1920.

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'Uh l'lfT PATENT FFIGE.

HANS J. BENTSON, F WIN'II-IROP HARBOR, ILLINOIS, ASSIGNOR T0 FREDERICKC. AUSTIN, 0F CHICAGO, ILLINOIS.

TBENCHING-MACHINE.

anemia.

Specification of Letters Eatent.

Patented Jan. 6, 1192683.

Application filed'September 15, 1916. Serial No. 120,271.

To all whom it may concern:

Be it known that I, HANS J. BENTSON, a

I citizen of the United States of America, and resident of WinthropHarbor, Lake county,

Illinois, have invented a certain new and useful Improvement inTrenching-Machines, of which the following is a specification.

My invention relates to excavating n lchines of that kind in which amovable or traveling body is provided at its rear end with diggingapparatus for cutting a trench as the machine moves slowly forward.

The object of my invention is to provide an improved construction andarrangement whereby practically the entire machine, except theunder-frame and traction devices, is movable bodily sidewise, during theoperation of the digging apparatus, so that a trench may be formed whichis wider than the digging apparatus, thus making it possible to form awide trench without the necessity of widening the excavator.

It is also an object to provide certain details and features ofconstruction and combinations tending to increase the general eilLciencyand desirability of a trenching ma chine of this particularcharacter.

To the foregoing and other useful ends, my invention consists in mattershereinafter set forth and claimed.

In the accompanying drawings Figure 1 is a side elevation of anexcavator embodying the principles of my invention.

Fig. 2 is a plan view of a portion of said machine. V

Fig, 3 is an enlarged side elevation of those portions of the machineshown in Fig. 2, with certain parts shown broken away for convenience ofillustration.

Fig. 4 is a rear elevation of said machine, showing a cross-section. ofthe trench, and

illustrating howthe machine .cuts a trench.

which is wider than the digging apparatus. Fig. 5 is an enlarged planview of certain parts of the machine.

Fig. 6 is a cross-section on lined-6 in Fig. 5.

Fig. 7 is a cross-section on line 7-7 in Fig, 5.

Fig. 8 is a cross-section on line 8-8 in Fig. 5.

Fig. 9 1s a detail sectional view showing the clutch mechanism forcontrolling the in termittent forward movement of the excavator.

I Fig. 10 is a side elevationof the mechanish shown in Fig. 9, being anenlarged section on line 10-10111 Fig. 5.

Fig. 11 is a cross-section on line 1l11 in Fig. 4.

Fig. 12 is a diagrammatic View showing the manner in which the earth isremoved by successive forward and sidewise cuts to form the trench.

Fig. 13 shows-a modification of the mechanism for automaticallycontrolling the intermittent forward movement of the machine.

As thus illustrated, my invention comprises an under-frame A mounted oncaterpillars B, or other suitable traction devices, and provided withfront wheels C, whereby the machine may move forward in the di rectiondesired for the trench. The body D is disposed immediately above theunderframe A, and is provided with longitudinally disposed shafts E andF having rollers or wheels 1 which engage the transverse tracks '2 onthe under-frame, it being understood that said shafts are mounted insuitable bearings on said body. With this construction the entiremachine, except the under-frame and the traction devices, is movablebodily sidewise. The body D is provided with a frame (Z provided withbearings of any suitable character for supporting the rear transverseshaft 3 which supports the upper end of the digging beam G, the latterbeing of any suitable or desired form, and provided with endless chains9 having digging buckets & for cutting the trench. These chains 9 aresupported on sprockets or other rotary members mounted on the shaft 3and at the lower end of the digging beam. In this way, the beam G isadapted to swing up and down about the horizontal and transverse axisprovided by the shaft 3, and anysuitable means, such, as the cable 5 andsheaves 6 and 7, can be employed for hoisting the beam out of theground. The sheave 6 is suitably mounted on they digging beam, and; thesheave 7 is suitably mounted on the frame d, and the hoisting cable 5can be operated by any suitable means. A. rack-bar H extendstransversely-of-the trench, cross-wise of the digging beam Gr, sothatthe latter is adapted with means for engaging the sides of the Nil)the beam G, being mounted in suitable beartof 'are driven by sprocketchains 5 from the ings thereon, and is provided at its'lower end with apinion 9 for engaging sald rackbar, whereby rotation of this shaft willshift the beam and buckets laterally on said rackbar, from one side ofthe trench to the other, in the desired manner. For this purpose, theshaft F is provided with a rear telescoping extension f, and with auniversal joint 10, whereby this extension can swing up and down withthe digging beam. The rear end of this extension 7 is'provided with abevel pinion 11 for engaging the bevel gear 12,

which latter in turn engages the bevel pinion 13 on the upper end of theshaft 8,'s0 that the rotation of the shaft F is in this way communicatedto the shaft 8 when the body D is shifted sidewise in either direction.The belt 14 is suitably driven by an engine 6 or other motive power,carried on the body D, and rotates the pulley 15 on the transverse shaft16, which latter is provided with a sprocket connection 17 with theshaft 3, whereby the latter is driven to operate the buckets. This shaft3 is provided with loose bevelpinions 19 and 20 for engaging the bevelgear 21 on the upper end of the vertically disposed shaft 22, whichlatter is mounted in suitable bearings on the framework (5, in a mannerthat will be readliy untier-stood. The clutch member 23 on the shaft 3is movable into and out of engagement with the bevel pinions 19 and 20,there'- by to reverse the rotation of the vertical shaft 22, in a mannerthat will be readily understood. The lower portion of this shaft 22 isprovided with a worm 2a which engages a worm-wheel 25 on the shaft F,thus causing the latter to turn one way or the other, depending upon theposition of the clutch member 23, which latter thus controls theshifting of the excavator sidewise. In

order that the sidewise movement of the excavator may be positive andforcible in character, the shafts l't andl are provided with pinions 26for engaging the racks 27 which extend parallel with the tracks 2 on sheunder-frame, The traction devices B square shaft 28 which is mounted torotate in suitable hearings on the under-frame A,

and which is driven by a sprocket connection' 29 with the transverseshaft 30 mounted in suitable bearings on the body I) which is movablesidewise. @aid body D is provided with rigid portions 31 at each side ofthe sprocket for the connection 29, so that the latter slides sidewiseon the shaft 28, when the body is shifted from one side to the other.The shaft 30 is driven by a connection 32 with the 33, which latter ismounted in suitable hearings the body D, and this 33 is in turn drivenby a gear connection 3st the adjacent shaft mantis nects the shaft 35with the shaft 37, which latter is mounted. in bearings-on the bodydirectly below the shaft 16, and power is transmitted from the shaft 16to the shaft 37 through a gear connection 38 of anysuitable character.This gear connection 38 has a clutch 39 on the shaft 37, and by openingand closing this clutch the power-transmitting connection between theengine and the traction devices B is opened and closed.

The machine thus far described can be used for making a trench, in themanner indicated in F ig. 12, by simply controlling theclutches 23 and89 in any suitable or desired manner, so that the machine will firstmove ahead the desired distance, while the shafts E and F to shift themachine sidewise on the tracks 2, in a manner that will be readilyunderstood. This lateral shifting of the machine will produce one of thecuts Y, and is made by the gradual sidewise movement of the bucketswhile they are being operated up and down on the digging beam. As soonas the buckets have reached the limit of this sidewise out, which is theside of the wide trench, the clutch 23 is then moved to a middleposition between the two bevel pinions 19 and 20, thus stopping thesidewise movement. The clutch 39 is then again closed, with the resultthat another forward cut X is then made at the opposite side of the widetrench. Tn this way, the operation proceeds by first a narrow forwardcut at one side of the wide trench, then a sidewise out toward the otherside of the trench, and then a forward cut at this side of the trench,followed by a sidewise out toward the side of the trench where the firstforward cut was made, and so on until the wide trench is finished.

As a matter of further and special improvement, however, the clutches 23and 39 are automatically controlled as follows: The clutch 23 has apivoted shifting lever it) which extends downward to engage thecam-plate 4H. This cam-plate is mounted to slide in longitudinal guides42 on the body D, and said plate is provided with two oppositelyformedcams 3 and 44lfor engaging the roller 45 on the lower portion ofsaid lever, whereby the latter is rocked end of the machine, so

iea'aeie from one side to the other about its axis 46, when the plate ispulled forward. Said plate is connected by a link 47 with an arm 48 ofthe rock-shaft 49, which latter is arranged transversely of the machineand mounted in suitable bearings on the body D, as shown more clearlyinFig. 7, and is provided with an upstanding arm 50 at its other end. Thesprocket chain 36 is provided with a laterally projecting pin 51arranged in position to engage the arm 50 when this pin travels towardthe forward that the shaft 49 will be rocked to pull the plate 41forward and thereby shift the clutch 23 into engagementwith either oneor the other of the bevel p'inions 1.9 and 20, depending upon which ofthe two cams 43 and 44 is brought into engagement with the roller 45, ina manner that will be readily understood.

The lower end of the lever slides on a rod 52 which is mountedtransversely on the .undrs' frame of the machine, and which is providedwith stops 53, whereby the lever 40 is operated whenever the body of.the machine reaches the limit of its sidewise movement in eitherdirection, so that the clutch member 23 is automatically shifted tomiddle or neutral position between the two bevel pinions l9 and 20, thusstopping the rotation of the shaft 22, and thereby leaving the machinein its laterally shifted position. The clutch 39 is operated by abellcrank 54 which has a roller 55 for engaging the cam track 56, thelatter having its ends deflected forward to form the cams 57, thiscam-track being simply a bent channel-iron. At about the same time thatthe body D of the machine reaches the limit of its sidewise movement, sothat the lower end-portion of the lever 40 is operated by one of thestops 53, the roller 55 encounters one of the earns 57, whereby theclutch 39 is closed to cause the rotation of the shaft 37,

' thus causing the rotation of the square shaft 28 by which the tractiondevices are operated to move the machine forward. To do this the stops53 must, of course, be adjusted in proper position on the rod 52, sothat they will engage the lever 40 at the proper times and in a mannerto produce the mode of operation stated. This forward movement of themachine continues, it will be seen, until the pin 51, previouslydescribed, strikes the lever-arm 50 on the rockshaft 49, thereby movingthe plate 41 forward and causing a shifting of the lever 40, with aconsequent engagement of the clutch memher 23 with one of the bevelpinions 19 or 20, so that the rotation of the shaft 22 is started forthe purpose of rotating the shafts E and T to shift the body D towardthe other side of the machine, causing the buckets to make a sidewisecut away from the forward cut which was made while the traction devicesto the other side of the point formed by B were inoperation. The forwardmovement ceases, of course, immediately after the beginning of thereturn sidewise motion and as soon as the clutch 39 is opened again bydisengagement of the roller from the cam 57. The shaft 49 has adownwardly extending arm 58 provided with a spring 59 arranged tooperate said shaft in a direction to push the plate 41 backward as soonas the arm 50 is released by the pin 51 so that said plate will alwaysstand in position to be pulled forward to operate the lever 40 each timethemachine reaches the limit of one of its forward movements. Thearrangement and adjustment of the parts must be such, obviously, thatwhen lever 40 is operated a distance by a stop 53, thus stopping thelateral motion of the body, the operation leaves the roller 45 just alittle the cams 43 and 44, so that when plate 41 is pulled forward theroller 45 will engage the proper cam to carry the lever the balance ofthe distance'necessary to reverse the clutch 23 in the manner explained.

From the foregoing, it will be seen that with the construction shown anddescribed a comparatively na'rrow trenching machine can be used formaking a very wide trench, by a series of forward and sidewise cuts, asshown in Fig. 12, so that it will not be necessary to, widen the machineobjectionably 1n order to produce a wide trench. The back-and-forthsidewise movements of the machine alternate with periods or intervals ofrest, and the forward movements occur during these intervals ofcessation of the lateral movements.

As shown in Fig. 13, a bar 60 extends transversely of the machine, beingmounted on the under-frame A in any suitable manner. This bar isprovided with cams 61 which are adjustable longitudinally thereof, andwhich take the place of the cams 57 previously described. With thisconstruction, and by adjusting these cams 61 toward and away from eachother, and with the stops 53 located in difierent positions on therod'52 (see dotted positions in Fig. 5). the

width of the trench can be varied to suit the r requirements in anyparticular case. Ad justment of the cams 61 will, of course, requirereadjustment of the steps 53, as the lever 40 will travel sidewise moreor less according to the width desired for the trench.

The forward movements'of the excavator overlap each other at the middleof the wise at the same speed that 'underfframe having traction to thewidth of a trench, (see F igr12), and these slices Y are distinct andseparate from the forward cuts X, the sidewise and forward movementsofthe excavator being distinct and independ' ent of each other. With thisconstruction and method of operation, a single machine is capable ofmaking trenches of different widths, and the digging apparatus can be ofa width to make a very narrow trench, if desired. Thus,alarger andbroader field of utility is insured for the machine, as it is capable ofmaking either anarrow-or a wide trench; and, although the digging'beam Gmay be quite narrow, still the means pro vided for pushing on the sidesof the trench I (see Figs. 4 and 11) insures against breakage andstraining of the beam, as the lower portion of the beam itself ispropelled sideits upper portion is moved sidewise in either direction.

What if claim as my invention is 1. An excavating machine comprising andevices, a body mounted on said under-frame to move bodily sidewisethereon, digging apparatus carried at the rear end of said body, meansfor operating said digging apparatus while said devices are in operationto move the excavator slowly forward, thereby to produce a forward cutin the ground, mechanism to shift said body laterally during theoperation of said apparatus and while devices are stationary to producea sidewise cut away from said forward cut, thereby to form a trench thewidth of which is equal forward cut plus the length of the'sidewise out,said apparatus comprising a beam arranged to swing up and down about ahorizontal and transverse .axis at the upper end thereof, and means i inthe trench to propel the beam sidewise in unison with th wise movementof said body.

2. An excavating machine comprising an under-frame having tractiondevices, a body mounted on said under-frame to move bodily sidewisethereon, digging apparatus carried at the rear end of said body, meansfor operating said digging apparatus while said devices are in operationto move the excavator slowly forward, thereby to produce a forward cutin the ground, mechanism to shift said body laterally during theoperation of said apparatus and while said devices are stationary toproduce a side-, wise cut away from. said forward cut, thereby to form atrench the width of which is equal to the width of, a forward cut plusthelength of the sidewise cut, said apparatus comprising an endlessseries of buckets which travel upward in loading position to produce thesuccessive cuts which form the trench, and means in the trench to propelsaid buckets sidewise in unison with the sidewise movement of said bodyaway from said restate 3. An excavating machine comprising anunder-frame having traction devices, a body mounted on said under-frameto move bodily sidewise thereon, digging apparatus carried at the rearend of said body, means for operating said digging apparatus while saiddevices are in operation to move the excavator slowly forward, therebyto produce a forward cut in the ground, and mechanism to shift said bodylaterally during the operation of said apparatus and while said devicesare stationary to produce a sidewise cut away from said forward cut,thereby to form a trench the width of which is equal to the width of aforward cut plus the length of the sidewise out, said appaend of saidshaft to engage said rack-bar,

and means for connecting said shaft with said mechanism to propel saidbeam side wise in unison witl the sidewise movement of said body. i

4. An excavating machine comprising an under-frame having tractiondevices, a digging apparatus mounted on said underrame, so that a trenchwill be cut in rear of said under-frame when said devices are operatedto move the entire .machine forward, means including mechanism forpushing on the sides of the trench for shifting said apparatus back andforth laterally thereof to widen the trench, means for causing intervalsof rest between said back-andforth lateral movements of said apparatus,and means for automatically causin predetermined forward movements of te entire machine during. said intervals of rest.

5. An excavating machine comprising an under-frame having tractiondevices, a body mounted on said under-frame to move bodily sidewisethereon, digging apparatus carried at the rear end of said body, meansfor operating said digging apparatus in the ground while said body isstationary on said under-frame and while said devices are in operationto move the excavator slowly for-- of said apparatus in'the ground andwhile said devices and under-frame are stationary to produce a sidewisecut by horizontal movement of stud digging apparatus bodily out and bymove'iltt is equal to the width of a forward 'cut plus the length of thesidewise cut having means for stopping said lateral movement while themachine is moving forward.

6. An excavating machine as specified in claim 5, said mechanismcomprising transverse racks on said under-frame and pinions on said bodyto engage said racks.

7 An excavating machine as specified in claim having means toautomatically start and stop the operation of said mechanism, andautomatic means to start and stop the operation of saidtraction devices,so that the forward cuts alternate automatically with the lateral cuts.

8. An excavating machine as specified in claim 5, having means start andstop the operation of said devices, so that no forward movement occurswhile the body is moving sidewise, and automatic means to start and stopthe operation of said mechanism, so that lateral movement isautomatically prevented while the machine is moving forward;

9. An excavating machine as specified in claim 5, having automatic meansto start and stop the operation of said traction devices, and automaticmeans to start and stop the operation of said mechanism, so' that saidbody, is automatically held stationary on said under-frame while theexcavator is moving forward, and whereby the excavator is automaticallycontrolled, while said apparatus is at work in the ground, to producethe successive forward and sidewise cut which form the trench.

10. An excavating machine as specified in claim 5, and adjustable meansto control said mechanism at will to vary the width of the trench.

11. An excavating machine comprising an under-frame having tractiondevices, a diging apparatus mounted on said underrame, so that a trenchwill be cut in rear of said under-frame by horizontal movement of saidapparatus bodily when said devices are operatedto move the entiremachine forward, mechanism to shift said apparatus bodily andhorizontally and laterally thereof in one direction transversely of thetrench while the machine is standing still and while said apparatus isoperating in the ground thereby to make a straight transverse cut in theground, means to automatically stop said lateral movement, means toautomatically start the operation of said-devicesto move the machineforward a distance after the ,lateral movement has ceased and while saidapparatus is still operating in the ground, whereby the lateral movementis interrupted at about the. time the forward movement is started, meansto paratus laterally to automatically devices are operated to moveautomatically reverse said mechanism to return said apparatus laterallyin the opposite direction, said forward horizontal movement beingautomatically stopped at about the time the return sidewise movement isstarted, so that no lateral movement occurs while the machine is makinga straight forward cut in the ground, and provisions to automaticallystop said return lateral movement and again start the forward movementwhen said apparatus reaches the limit of said return movement, wherebythe excavation progresses in the line of direction of the ditch bylongitudinal movements of said apparatus automatically alternating withtransverse movements thereof.

12. An excavating machine comprising an under-frame having tractiondevices, a digging apparatus mounted on said underframe, so that atrench will be cut in rear of said underframe by horizontal movement ofsaid apparatus bodily when said devices are operated to move the entiremachine forward, mechanism to shift said apparatus bodily andhorizontally'and laterally thereof in one direction transversely of thetrench while the machine is standing still, thereby to make a straighttransverse cut in the round, means including a clutch controlled by thelateral shiftingof said apparatus to automatically stop said lateralmovement thereof, means including a clutch" controlled the lateralshifting of said apparatus to automatically start the operation of saiddevices to move the machine forward a dis loo tance after the lateralmovement has ceased, and while said apparatus is still operating in theground, so that the lateral movement is interrupted at about the timethe forwardmovement is started, means for controlling 5 said firstmentioned clutch to automatically reverse said mechanism to return saidapparatus late ally in the opposite direction, said forward horizontalvmovement being automatically stopped by said last mentioned clutch atabout the time the return lateral movement is started, and provisions toautomatically stop said return lateral movement and again start theforward movement when said apparatus reaches the'limit of said ree turnmovement, so that no lateral movement occurs while the machine "ismaking a straight forward cut in the ground, whereby the excavatorprogresses in the line of direction of-the ditch by longitudinalmovements of saidrapparatus automatically alternating with transversemovements thereof.

13. An excavating machine comprising an under-frame having tractiondevices, a digging apparatus mounted on said underframe, so that atrench will be cut in rear of said under-frame, by horizontal movementof said apparatus bodily when said the entire ma chine forward,mechanism including means to push against the side of the trench toshift said apparatus bodily and horizontally and laterally thereof inone direction transversely of the trench while the machine is standingstill, means to automatically stop said lateral movement, means toautomatically start'the operation of said devices to move the machineforward a distance after the lateral movement has ceased, and while saidapparatus is still operating in the ground, so that the lateral movementis interrupted at about the time the forward movement is started, meansto automatically reverse said mechanism to return said apparatuslaterally in the opposite direction, said forward horizontal movementbeing automatically stopped at about the time the return lateralmovement is started, and provisions to automatically stop said returnlateral movement and again start the forward movement when saidapparatus reaches the limit of said return movement, whereby theexcavation progressesin the line of direction of the ditch bylongitudinal movements of said apparatus automatically alternating withtransverse movements thereof.

14:. An excavating machine comprising an under-frame having tractiondevices, a digging apparatus mounted on said underframe, so that atrench will be cut in rear of said under-frame by horizontal movement ofsaid apparatus bodily when said devices are operated to move the entiremachine forward, mechanism to shift said apparatus bodily andhorizontally and laterally thereof in one direction transversely of thetrench while the machine is standing still, a power plant to operate theentire machine and mounted to shift laterally with said apparatus, meansincluding a clutch controlled by the lateral shifting of said apparatusto automatically stop said lateral movement thereof, means including aclutch controlled by the lateral shifting of said apparatus toautomatically start the operation of said devices to move the machineforward a distance after the lateral movement has ceased, and while saidapparatus is still operating in the round, so that the lateral movementis interrupted at about the time the forward movement is started, meansto automatically reverse said mecha nism vto return said apparatuslaterally in the opposite direction, said forward horizontal movementbeing automatically stopped at about the time the return lateralmovement is started, and provisions to control said clutches and therebyautomatically stop said return'lateral movement and again start theforward movement when said apparatus reaches the limit of said returnmovement, whereby. the excavation progresses in the line of direction ofthe ditch by longitudi- 4 frame,

neaaei'e nal movements of said apparatus automati cally alternating withtransverse movements thereof. I

15. An excavating machine compr sing an under-frame having tractiondevices, a digging apparatus mounted on said .underso that a trench willbe cut in rear of said under-frame by horizontal movement of saidapparatus bodily when said devices are operated to move the entiremachine forward, means for shifting said apparatps back and forthhorizontally and bodily and laterally thereof to widen the trench, saidapparatus being adapted to make a straight transverse out in the groundwhen moved laterally, means for causin intervals of rest between saidback-andorth lateral movements of said apparatus, and means forautomatically causing predetermined horizontal forward movements of theentire machine and thereby forming straight forward cuts in the groundduring said intervals of rest,

'16. An excavating machine comprising an under-frame having tractiondevices, a digging apparatus mounted on said underframe, so that atrench will be cut in rear of said'under-frame when said device areoperated to move the entire machine forward, means for shifting saidapparatus back and forth horizontally and bodily and laterally thereofto widen'the trench, said apparatus being adapted to make a straighttransverse cut in the ground when moved laterally, means forautomatically causing intervals of rest between said back-andforthlateral movements of said apparatus, and means for automatically causingpredetermined horizontal forward movements of the entire machine andthereby forming straight forward cuts in the ground during saidintervals of rest.

17. An excavating machine'comprising an under-frame having tractiondevices, a digging apparatus mounted on said underframe, so that atrench will be cut in rear of said under-frame when said devices areoperated to move the entire machine forward, means for shifting saidapparatus hack and forth horizontally and bodily and laterally thereofto widen the trench, a power plant connected to operate the entiremachine and mounted to shift laterally with said apparatus, means forcausing intervals of rest between said back-and-forth lateral movementsof said apparatus, and means for automatically causing predeterminedhorizontal forward movements of the entire machine during said intervalsof rest.

Signed by me at Chicago, Illinois, this 6th day of September, 1916.

HANS J. BENTSUN.

